Device for shaping sand molds in casting machine

ABSTRACT

A device for shaping sand molds used in casting comprises a central frame which is adapted to be filled with the sand which is to be shaped from an overhead hopper. A rear frame is spaced from the central frame and guide tubes arranged therebetween on which is movable an intermediate frame. The same guide means provide a guide for an outer frame arranged on the other side of the central frame from the intermediate frame which is also movable on the guide means toward and away from the central frame. The sand is molded by movement of the intermediate and outer frames toward the central frame to compress the sand material therein and to form it into a desirable casting mold shape.

United States Patent [1 1 Otaki [54] DEVICE FOR SHAPING SAND MOLDS IN CASTING MACHINE [76] inventor: Shigeji Otaki, 508-1 Aza-ldenoue Tainoshima Tamukae-cho, Kumamoto, Japan 22 Filed: Jan. 13, 1972 211 App]. No.: 217,460

[52] US. Cl 164/187, 164/130, 164/207 Wells et al. 164/129 X [451 Apr. 9, 1974 Primary Emminer-Robert D. Baldwin Attorney, Agent, or Firm-McGlew and Tuttle "[5 7] ABSTRACT A device for shaping sand molds used in casting comprises a central frame which is adapted to be filled with the sand which is to be shaped from an overhead hopper. A rear frame is spaced from the central frame and guide tubes arranged therebetween on which is movable an intermediate frame. The same guide means provide a guide for an outer frame arranged on the other side of the central frame from the intermediate frame which is also movable on the guide means toward and away from the central frame. The sand is molded by movement of the intermediate and outer frames toward the central frame to compress the sand material therein and to form it into a desirable casting mold shape.

4 Claims, 3 Drawing Figures wmmm 9 914 I r 3,802,486

SHEET 2 OF 3 PATENTEDAFR 9 1914 SHEEI 3 0F 3 FIG.

DEVICE FOR SHAPING SAND MOLDS IN CASTING MACHINE BACKGROUND OF THE INVENTION Field of the Invention This invention relates in general to the construction of molding machinery and, in particular, to a new and useful device for shaping sand molds which are to be used in a casting machine and which comprises, a stationary mold frame defining a pressure chamber which is filledwith the sand material to be molded and a frame guided for movement on each side of the stationary frame toward and away therefrom for compressing the sand into a desired mold shape within the central stationary. mold.

This invention relates to a device for shaping sand molds used in casting wherein the raw material sand charged in a compression pressure chamber which is pressurized from the lateral direction to shape sand molds. The thus formed sand molds are compacted by pressure applied from each side so that the formed mold is tightly compacted.

Generally, in a casting machine of this type a sand mold has heretofore been formed by fixing a mold plate at one side and applying pressure on a mold plate at another side. In the sand mold thus formed the hardness on one side surface differs from that on the other side surface, and therefore it has been difficult to obtain a product of good quality.

According to the present invention, since the sand mold is pressed from both sides, a formed sand mold having uniform hardness is obtained, and castings of good quality can be obtained. The thus formed sand molds are successively tightly adhered and extruded on the casting base. Thus, since a number of sand molds may be aligned on the casting base, it is possible to pour molten metal into these sand molds, and therefore the device according to the present invention has very high working efficiency.

Accordingly, it is an object of the invention to provide an improved device for forming sand molds which comprises a central mold frame defining a pressure chamber for receiving the sand material to be molded and with a frame mounted for guiding movement on each side of the central frame which are movable together toward the central frame for shaping the sand in the central frame into the desired casting shape.

FIG. 1 is a side elevation showing the essential part of the device according to the present invention;

FIG. 2'is a front elevation showing the same; and FIG. 3 is a cross sectional viewshowing a formed sand mold.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENT This invention is to provide a device wherein raw material sand charged in a compression pressure chamber is pressed and compressed from both forward and rear surfaces with a forward fitting plate and a rear fitting plate respectively provided with shaping molds thereby to form a sand mold, which has uniform hardness and. no hardness unevenness, and hence castings of good quality are obtained. 7

More specifically, in the device according to the present invention, stationary frames are provided at the central part and the rear part of the machine main body. A compression pressure chamber is formed in the central stationary frame and a raw material sand tank communicates therewith through a pinch valve.

provided in the upper end opening of said tank to control the supply of raw material sand. A movable frame is arranged in the front part of said central stationary frame and guide shafts are disposed in the four corners of said movable frame which penetrate through guide tubes of a central stationary frame and intermediate movable frame. The guide shafts are held on the four corners of the rear stationary frame through bearings, said foreward movable frame and intermediate movable frame are arranged to move back and forth by a pair of separate oil-pressure cylinders mounted on the machine main body. A forward shaping mold fitting plate is mounted on said forward movable frame such that it is freely rotatable upwardly using the upper end edge as a pivot. The rear shaping mold fitting plate is capable of extruding the formed sand mold to the forward carrying path through an extruding cylinder fitted to the intermediate movable frame; and, when it is pulled back to the rear part, the rear leg of the rear shaping mold fitting plate is received by the surface of said intermediate movable frame. A clearance is retained between said each movable frame and floor surface of the machine main body to make it movable. Movement of these movable frames, application of pressure thereto, and extrusion of the sand mold, rotation of forward fitting plate, etc. are arranged to be made through oil-pressure or air pressure cylinders. This permits the continuous forming of tightly adhering sand molds and their positioning onto the carrying path so as to permit rapid pouring of molten metal.

In the drawings, reference numeral 1 designates a machine main body, and a central stationary frame 2 is mounted on the central portion of the main body and a rear stationary frame 3 on the rear part thereof. The centralstationary frame 2 has a side wall portion 8 forming a compression pressure chamber. A raw material sand tank 9 communicates through a pinch valve with at the upper part the compression chamber. A switching valve 10 operated by an air cylinder 16, is provided at the opening of the upper end surface of said tank 9, whereby a predetermined amount of raw material sand is supplied in said tank 9. On the other hand, a forward movable frame 6 is disposed at the front part of said central stationary frame 2. At each corner portion of said forward movable frame 6, guide shafts ll, 11, are attached and these guide shafts respectively penetrating through holes 12, 12, at four corner portions of the central stationary frame 2 and further through guide tubes 14, 14, connecting four corner portions of rear stationary frame 3, and supported by bearings 13, 13, at four corner portions of the rear stationary frame. Furthermore, atthe forward movable frame 6 a forward surface fitting plate 4 for attaching a forward surface shaping mold is disposed. The forward fitting plate 4 is rotated upward using the upper end surface as a pivot by means of an oilpressure cylinder 15 disposed at the side of said movable frame thereby to communicate the floor surface of the machine main body with the carrying base. The forward fitting plate 4 provided with the forward surface shaping mold is movable back and forth together with the forward movable frame 6 by means of an oilpressure cylinder 17 to form the forward surface portion of the compression pressure chamber of said central stationary frame 2. At the front part of said intermediate movable frame 7 supported by guide tubes 14, 14 connecting said central stationary frame 2 to rear stationary frame 3, there is arranged the rear surface fitting plate which is movable back and forth through an oil cylinder fitted in said intermediate movable frame 7, thereby to form the rear surface portion of the compression pressure chamber of said central stationary frame 2. The raw material sand charged in said compression pressure chamber 8 from the raw material tank 9 by light pressure air is applied with pressure from both forward and rear sides to shape sand molds and it has the configuration of each shaping mold at its forward and rear surfaces. The forward movable frame '6 is restored to the original position. The forward fitting plate 4 is rotated upward, and a path to the carrying base is opened, and the rear surface fitting plate 5 is extruded by the oil-pressure cylinder fitted to the machine main body to move up to the entrance of the carrying base.

ln this case, gaps are provided between each lower end surface of said forward movable frame 6 and intermediate movable frame 7 and the floor surface of the machine main body to prevent wear and damage of the floor surface due to the migration of these frames. Thus, a predetermined amount of the raw material sand charged in the compression pressure chamber is pressed from the forward and rear surfaces and therefore the hardness of sand mold thus formed becomes homogeneous at its forward and rear surfaces and thus products of good quality can be obtained from the use of the mold.

Thus, according to the present invention, sand molds of uniform hardness can be obtained in an extremely simple device by applying pressure from both forward and rear sides, thereby to obtain castings of good quality, and further by removing contact surface between each movable frame and floor surface shifting of formed mold is prevented.

What is claimed is:

l. A device for shaping sand molds comprising a central frame defining a pressure chamber within the frame for receiving the material to be molded, tubular guide means extending outwardly from said frame, a first movable frame guided for movement on said tubular guide means toward and away from said central frame, a second movable frame guided for movement on said guide means toward and away from said central frame, means to supply material to be molded to said central frame pressure chamber, and means to move said first and second frames toward said central frame from opposite sides thereof to compress the material therein to form it into a desired mold configuration, a rear frame spaced from said central frame, said tubular guide means comprising tubular members extending from said rear frame to said central frame, said first frame being arranged between said rear frame and said central frame and being guidable on said tubular guide members, said second frame being on the opposite side of said central frame from said first frame and having tubular portions guided on said tubular members, an actuator carried on said rear frame and connected to said first frame and comprising said means to move said first frame toward and away from said central frame, a pressure cylinder carried on said central frame and having a piston rod portion connected to said second frame and comprising said means to move said second frame toward and away from said central frame, a fitting plate pivotally carried on said second frame and being movable between a position in which it projects from said second frame toward said central frame to a position in which it is lifted upwardly above at least a portion of said second frame.

2. A device for shaping sand molds, according to claim 1, including a hopper arranged above said central frame containing the material to be molded, and valve means for opening and closing said hopper for regulating the discharge of material from said hopper into said central frame pressure chamber.

3. A device for shaping molds, particularly sand molds for casting machines, comprising a first stationary central frame, a rear frame substantially parallel to and spaced from said central frame, tubular guide members extending between the corner portions of said rear frame and said central frame, an intermediate frame engaged on said tubular guide portions between said rear frame and said central frame and being movable toward and away from said central frame, means on said rear frame connected to said intermediate frame for shifting said intermediate frame toward and away from said central frame, said central frame including wall means defining a pressure chamber for receiving the material to be molded, supply means mounted above said central frame for supplying material to be molded into said pressure chamber, an outer movable frame arranged on the opposite side of said central frame from said rear frame and said intermediate frame, a tubular guide member arranged in each corner portion of said outer frame and guided within the tubular guide members extending between said central frame and connected to said outer frame for shifting said outer frame toward and away from said central frame, said outer frame and said intermediate frame being movable toward said central frame to compress the material to be molded within said pressure chamber, a form plate carried on said outer frame, and means mounting said form plate for pivotal movement between a position at which it extends forwardly of said outer frame toward said central frame and provides a forming plate for forming the material in said central frame pressure chamber to a position in which it is pivoted upwardly.

4. A device for shaping molds, particularly sand molds for casting machines, according to claim 3, including fluid pressure operated means connected .to

said forming plate for pivoting said forming plate. 

1. A device for shaping sand molds comprising a central frame defining a pressure chamber within the frame for receiving the material to be molded, tubular guide means extending outwardly from said frame, a first movable frame guided for movement on said tubular guide means toward and away from said central frame, a second movable frame guided for movement on said guide means toward and away from said central frame, means to supply material to be molded to said central frame pressure chamber, and means to move said first and second frames toward said central frame from opposite sides thereof to compress the material therein to form it into a desired mold configuration, a rear frame spaced from said central frame, said tubular guide means comprising tubular members extending from said rear frame to said central frame, said first frame being arranged between said rear frame and said central frame and being guidable on said tubular guide members, said second frame being on the opposite side of said central frame from said first frame and having tubular portions guided on said tubular members, an actuator carried on said rear frame and connected to said first frame and comprising said means to move said first frame toward and away from said central frame, a pressure cylinder carried on said central frame and having a piston rod portion connected to said second frame and comprising said means to move said second frame toward and away from said central frame, a fitting plate pivotally carried on said second frame and being movable between a position in which it projects from said second frame toward said central frame to a position in which it is lifted upwardly above at least a portion of said second frame.
 2. A device for shaping sand molds, according to claim 1, including a hopper arranged above said central frame containing the material to be molded, and valve means for opening and closing said hopper for regulating the discharge of material from said hopper into said central frame pressure chamber.
 3. A device for shaping molds, particularly sand molds for casting machines, comprising a first stationary central frame, a rear frame Substantially parallel to and spaced from said central frame, tubular guide members extending between the corner portions of said rear frame and said central frame, an intermediate frame engaged on said tubular guide portions between said rear frame and said central frame and being movable toward and away from said central frame, means on said rear frame connected to said intermediate frame for shifting said intermediate frame toward and away from said central frame, said central frame including wall means defining a pressure chamber for receiving the material to be molded, supply means mounted above said central frame for supplying material to be molded into said pressure chamber, an outer movable frame arranged on the opposite side of said central frame from said rear frame and said intermediate frame, a tubular guide member arranged in each corner portion of said outer frame and guided within the tubular guide members extending between said central frame and connected to said outer frame for shifting said outer frame toward and away from said central frame, said outer frame and said intermediate frame being movable toward said central frame to compress the material to be molded within said pressure chamber, a form plate carried on said outer frame, and means mounting said form plate for pivotal movement between a position at which it extends forwardly of said outer frame toward said central frame and provides a forming plate for forming the material in said central frame pressure chamber to a position in which it is pivoted upwardly.
 4. A device for shaping molds, particularly sand molds for casting machines, according to claim 3, including fluid pressure operated means connected to said forming plate for pivoting said forming plate. 